Calculation of Values

Calculating values from 2 forms

I have searched high and low for examples on how to calculate values from multiple forms.

Im trying to calculate a running total from a staring balance field + deposit amount field + withdrawal field from 3 forms and display it in a Control Page, im in the process of creating an application that hopefully i can roll out to many members in the future and the formula above is an example of how majority of my field values are calculated. If i can get an example then it may help me to create further reports.

Thanks Chris